VSCode language extension for MeLan

This is a language extension package for VSCode to support the syntax of MeLan, the meta-language with Python backend.

Known Issues

TextMate grammars are not well suited to describing contiguous sequences of scopes spanning multiple lines, each with their own rules (e.g. Command > Options > Body). For this reason, the matching of commands, option groups, and body contents, are currently implemented with separate rules.

Hence the following issues:

1. Parentheses directly following a word character (letter, digit or underscore) may be wrongly interpreted as an option group:

    a( foo=5 )          # wrongly colored as option group

2. Body delimiters ({} [] <[]>) directly following a word charater, or a closing parenthesis, may be wrongly colored as well:

    a{ not a body }     # wrongly colored as body
    )[ not a body ]     # wrongly colored as body

The solution for these issues is to use the tilde character ~, which Melan replaces with an empty string during compilation:

    a~( foo=5 )
    a~{ not a body }
    )~[ not a body ]

Release Notes

[0.2.3] – 02-May-2020

• Revert to single rule for body environments (two rules created issues with nested commands).
• Adapt Melan to actually match the syntax highlighting (drop the indentation constraint).